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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Role in “bois noir” epidemiology of inter-row vineyard groundcover vegetation used for green manure
No full text‘Candidatus Phytoplasma solani’ (CaPsol), associated with grapevine ‘bois noir’ (BN), has a broad range of host plants and can be transmitted to grapevine by several insect vectors. Hyalesthes obsoletus Signoret, the main CaPsol vector in European and Mediterranean countries, feeds preferentially and completes its biological cycle on Convolvulus arvensis L. and Urtica dioica L., occasionally transmitting the phytoplasma to grapevine, a dead-end host for the pathogen. Recent studies evidenced that other weeds, naturally present within and around the vineyards, can play a role in BN spreading. This study investigated the role of eight groundcover plant species (Eruca sativa Miller, Sinapis arvensis L., Phacelia tanacetifolia Benth., Vicia sativa L., Vicia faba var. minor Beck, Trifolium incarnatum L., Trifolium alexandrinum L., Polygonum fagopyrum L.), commonly utilized for inter-row vineyard green manure in Franciacorta (North Italy), in BN epidemiology. The activities, conducted in the years 2019 and 2020 in two BN-affected vineyards in Gussago and Provaglio d’Iseo (Franciacorta), included: (i) monitoring and sampling groundcover plant species and C. arvensis (known host plant) in July, and symptomatic grapevines in September; (ii) total nucleic acids extraction followed by CaPsol-specific identification by nested PCR amplification of stamp gene; (iii) sequencing and bioinformatic analyses (comparison with stamp sequence variants dataset available in literature) of stamp amplicons obtained from symptomatic grapevines and groundcover plants. Molecular analyses were carried out on 341, 55, and 108 samples collected during the field surveys from groundcover plants, C. arvensis and symptomatic grapevines, respectively. Nested PCR allowed identifying CaPsol in 26 out of 341 (7.6%) groundcover plants, 14 out of 55 (25.5%) C. arvensis plants, and 83 out of 108 (76.9%) grapevines. Within groundcover plants, only E. sativa, V. sativa, and P. fagopyrum were found CaPsol infected. Based on nucleotide sequence analysis of stamp amplicons, CaPsol strains harboring three stamp sequence variants were identified in grapevines: St5, St19, and St30. The variant St19 was found exclusively in the analyzed grapevines. The variants St5 and St30 were found also in CaPsol strains infecting E. sativa (St5), P. fagopyrum (St5), V. sativa (St5, St30), and C. arvensis (St5), suggesting their possible involvement in CaPsol transmission routes to grapevine. Interestingly, previous study demonstrated that H. obsoletus survival on V. sativa and C. arvensis are comparable, reinforcing its association to BN epidemiology. Results from this and further studies can indicate how to select the groundcover plants for green manure mixture, excluding the species putatively involved in BN diffusion
Evaluation of biostimulant effectiveness in grapevine “bois noir” management
No full textThis work, carried out from 2017 to 2020, aimed to evaluate the effectiveness of four commercial products (Delfan plus, Phylgreen, Phylgreen Kuma, Vegenergy), whose use as biostimulants is allowed in organic farming, in the management of ‘bois noir’ (BN), a grapevine disease associated with 'Candidatus Phytoplasma solani'. The field trials were carried out in a Chardonnay BN-affected organic vineyard located in Gussago (Franciacorta, North Italy), monitored since 2012. In September 2017, the vineyard was monitored for grapevine yellows symptoms and a map reporting the phytosanitary state of each plant was created. Based on this map, four treated blocks (each one treated with one biostimulant), and one untreated (control) block were arranged. The activities, conducted from 2018 to 2020, included: (i) applications with the biostimulants from mid-April (10 cm long grapevine shoots) to the beginning of August (every two weeks (7 treatments/year); (ii) mapping and sampling of symptomatic and asymptomatic vines in September; (iii) extraction of total nucleic acids and molecular identification of 'Ca. P. solani' by nested PCR-based amplification of stamp gene; (iv) molecular characterization of phytoplasma strains by means of stamp gene nucleotide sequence analysis; (v) statistical analysis to evaluate any differences in the curative and preventive effect on BN-symptoms. The statistical analysis, conducted on the increase of symptomatic grapevines from 2017 (pre-treatment) to 2020 (cumulative effect of the treatments conducted from 2018 to 20), showed a significant decrease in symptomatic vines in the Delfan plus block (-4.5 percentage points) in comparison to the other blocks. The curative effect (percentage of recovered grapevines) was calculated considering the health status of symptomatic plants in 2017 over the following three years. Percentage of recovered plants in the Delfan plus block was higher than in all the other blocks, although the difference observed towards the block treated with Vegenergy and the untreated one was not statistically significant. The preventive effect was calculated considering the percentage of new symptomatic plants (grapevines showing symptoms for the first time) in the three-year period 2018-20. Statistical analyses did not reveal significant differences on the preventive effect observed in the different blocks. However, the percentage of new symptomatic grapevines in the block treated with Delfan plus was lower than in the other blocks. Molecular and bioinformatics analyses showed the presence of eight distinct 'Ca. P. solani' strains carrying different stamp gene variants (St1, St5, St8, St10, St16, St18, St19, St30). The statistical analysis showed a uniform distribution of such phytoplasma strains within the vineyard, reinforcing the evidence that the effect on BN incidence in the blocks is due to the action of the biostimulants and not to possible difference in the 'Ca. P. solani' strain virulence. Based on the obtained results, it emerged that a reduction in the percentage of symptomatic vines was observed exclusively in the block treated with Delfan plus. Further open field trials carry out in different grape growing areas and on different cultivars are necessary to confirm the effectiveness of biostimulants BN control
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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